The present invention relates generally to a stuffing method and apparatus for producing encased food products having substantially flat ends which are defined by discs disposed within the casing. In particular, the present invention relates to a method and apparatus which insures that the discs, which are releasably joined together prior to their insertion into the casing, are easily separable so that the discs can be selectively introduced into the stuffed casing during the stuffing cycle to form the flat terminal ends of the encased product.
U.S. Pat. No. 4,466,465 describes a casing article for use in making, on a continuous basis, flat ended stuffed casing products having generally the shape of a right circular cylinder. For this purpose, the discs are annular. However, it should be appreciated that other disc shapes are possible, such as oval or polygonal. A companion patent, U.S. Pat. No. 4,466,984 describes a joined pair of discs which are disposable coaxially about a stuffing tube and inside an unshirred portion of the casing to be stuffed. The joined discs, separated during stuffing, are passed over the discharge of the stuffing horn and into the stuffed casing to form the flat ends of the product. An apparatus using the discs of U.S. Pat. No. 4,466,984 and the casing article of U.S. Pat. No. 4,466,465 is generally described in these patents and in a co-pending application, Ser. No. 675,478. The disclosures of the aforementioned patents and patent application are incorporated herein by reference.
Briefly, the pair of annular discs are juxtaposed and are joined together by a mechanical connection, such as a snap fit, which holds the discs in a face-to-face relationship. The discs are slightly spaced apart so that when they are in a proper position proximate to the discharge end of the stuffing horn, the stuffing pressure at the start of the stuffing operation will build up pressure between the discs and cause them to separate cleanly. One disc of the pair moves forward with the casing being stuffed so as to form the flat leading end of the stuffed casing. The trailing disc of the pair remains in position on the stuffing horn until the desired length of casing is stuffed. This trailing disc subsequently is moved off of the horn and into the stuffed casing at the end of the stuffing operation to form the flat trailing end of the stuffed casing, thereby forming the flat ended encased product.
The problem is that, at times, the discs may not separate cleanly responsive to the stuffing pressure. One reason for this is that manufacturing tolerances are such that the snap fit of one pair of discs may be tighter than the snap fit of another. Other attachment means can be used, such as an adhesive or break away means. However, the separation of these alternate means also may be difficult to control, and care is needed in order to insure a clean and even separation within a desired range of stuffing pressures. Separation is also hindered when the product being stuffed has a chunky consistency with a minimum of liquid or emulsion component. With such products the flow of liquid or emulsion into the space between the discs may be insufficient to cause the proper separation.
When the discs fail to separate, the stuffing pressure may push the connected pair forward and away from the stuffing tube so that both discs will be at the same end of the encased product. Consequently, the product will have only one flat end. Also, when both discs are pushed forward of the stuffing tube, the food product can back flow around and over the stuffing tube. This requires a shutdown for cleaning and thereby disrupts the stuffing cycle. If the discs separate but the separation is not clean and even around the entire periphery of the discs, the leading disc may tilt with respect to the stuffing axis. This would cause one end of the encased product to have an end which is not perpendicular to the longitudinal axis of the product. In this case the product will not be the shape of a right circular cylinder.
Accordingly, an object of the present invention is to provide means for insuring the proper separation of the joined pair of discs. This is accomplished according to the present invention by bending or warping the generally flat discs, which weakens the connection and causes separation of the discs or facilitates the subsequent separation of the discs responsive to a minimal stuffing pressure. The discs are fairly resilient so that when the warping forces are released, the disks return to their substantially flat orientation. In a preferred embodiment, warping or bending the discs, with respect to the generally flat plane of the discs, is accomplished by directing opposing members against each disc at staggered spaced intervals about the disc periphery.